She was open to seeing a doctor, but Chloe was worried that people would judge her if she had a formal diagnosis.

“All my teachers throughout elementary and high school said I was a distraction in class,” she explained.

It wasn’t until she had a formal evaluation that Chloe discovered she had ADHD, along with anxiety and depression. Chloe has since been diagnosed with a personality disorder as well.

The diagnosis wasn’t a shock.

“I believe I’ve had it since I was a child,” she said. “All my report cards talk about my focus and attention span.”

What it feels like to have ADHD

The symptoms aren’t the same for everyone, but ADHD is often debilitating.

“Often, it’s kind of like living in a fog… The way it’s been described to me is like everything almost looks blurry physically,” said Dr. Doron Almagor, a child, adolescent and adult psychiatrist and director of The Possibilities Clinic in Toronto.

“When you have a conversation, you lose track. You’re at work and you forget what you’re doing.”

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People with ADHD can also experience issues with their working memory, which means they’ll walk into a room and forget why they’re there.

“Brains with ADHD aren’t working at full capacity,” said Almagor. “That’s why, often, the medications we have for ADHD stimulate the brain to make it active and bring them to normal levels of activity and attention.”

Most people have some or all of these symptoms at some point in their lives, which can make it difficult to know when it’s actually ADHD.

“When people don’t know about it, don’t get noticed and it goes undiagnosed,” he said. “A lot of people get missed.”

Unfortunately, any delay in treatment can lead to anxiety and depression — as it did with Chloe.

The underdiagnosis of ADHD disproportionately affects girls and women because the disorder usually affects them differently, he continued. Girls don’t typically display “hyperactive” symptoms, making it less visible.

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“Teachers don’t see it, and are considered inattentive instead,” said Almagor. In his experience, most adults only realize that they might have ADHD after their child is diagnosed.

Treating adults is more complicated

When a child is suspected to have ADHD, a battery of psychological tests is performed. Parents and teachers are interviewed, and several doctors are involved.

“Then we do a differential diagnosis… to rule out anything else that might be mimicking the symptoms of ADHD,” said Bernhardt. “You want to rule out learning disabilities, anxiety, depression, childhood trauma… all that kind of stuff.”

ADHD commonly coexists with other disorders so the tests need to be extremely thorough in order to determine if ADHD is actually present.

Then doctors will try to determine the severity of the child’s ADHD.

“It’s much more than attention,” she said. “It can be problems with over-focusing as much as under-focusing or switching focus… it’s not a 15-minute doctor’s visit.”

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In adults, this process is much more complex. For starters, doctors have access to less information by way of report cards, teachers and parents. Sometimes, all they can do is interview the adult themselves.

There are more things to tease out, according to Bernhardt. Doctors will often look to significant others or past report cards, if the patient still has them, for any signs that ADHD has long been an issue for the patient.

“Adults with ADHD… aren’t usually the most accurate at quantifying or describing their impairments,” she said. This is because these adults have gone their entire lives with ADHD so they figure it’s “normal,” Bernhardt explained.

“It’s the only reality somebody with ADHD has ever had,” she said. “They don’t see it as an impairment.”

Most adults with ADHD will have struggled their whole lives with school, and sometimes, they have already been treated for anxiety, depression or substance abuse.

More awareness is needed

In order for patients to avoid developing other disorders in adulthood, doctors are focused on catching more diagnoses during childhood.

For that, there needs to be more education and awareness about the trials and tribulations of having ADHD, Almagor says.

“More doctors are being trained in it, for sure, but there’s still a gap,” said Almagor.